Trait Inspect

pub trait Inspect<AccountId> {
    type ItemId: Parameter;

    // Required method
    fn owner(item: &Self::ItemId) -> Option<AccountId>;

    // Provided methods
    fn attribute(_item: &Self::ItemId, _key: &[u8]) -> Option<Vec<u8>> { ... }
    fn custom_attribute(
        _account: &AccountId,
        _item: &Self::ItemId,
        _key: &[u8],
    ) -> Option<Vec<u8>> { ... }
    fn system_attribute(_item: &Self::ItemId, _key: &[u8]) -> Option<Vec<u8>> { ... }
    fn typed_attribute<K, V>(item: &Self::ItemId, key: &K) -> Option<V>
       where K: Encode,
             V: Decode { ... }
    fn typed_custom_attribute<K, V>(
        account: &AccountId,
        item: &Self::ItemId,
        key: &K,
    ) -> Option<V>
       where K: Encode,
             V: Decode { ... }
    fn typed_system_attribute<K, V>(item: &Self::ItemId, key: &K) -> Option<V>
       where K: Encode,
             V: Decode { ... }
    fn can_transfer(_item: &Self::ItemId) -> bool { ... }
}

Trait for providing an interface to a read-only NFT-like item.

Required Associated Types

type ItemId: Parameter

Type for identifying an item.

Required Methods

fn owner(item: &Self::ItemId) -> Option<AccountId>

Returns the owner of item, or None if the item doesn’t exist or has no owner.

Provided Methods

fn attribute(_item: &Self::ItemId, _key: &[u8]) -> Option<Vec<u8>>

Returns the attribute value of item corresponding to key.

By default this is None; no attributes are defined.

fn custom_attribute( _account: &AccountId, _item: &Self::ItemId, _key: &[u8], ) -> Option<Vec<u8>>

Returns the custom attribute value of item corresponding to key.

By default this is None; no attributes are defined.

fn system_attribute(_item: &Self::ItemId, _key: &[u8]) -> Option<Vec<u8>>

Returns the system attribute value of item corresponding to key.

By default this is None; no attributes are defined.

fn typed_attribute<K, V>(item: &Self::ItemId, key: &K) -> Option<V>

where K: Encode, V: Decode,

Returns the strongly-typed attribute value of item corresponding to key.

By default this just attempts to use attribute.

fn typed_custom_attribute<K, V>( account: &AccountId, item: &Self::ItemId, key: &K, ) -> Option<V>

where K: Encode, V: Decode,

Returns the strongly-typed custom attribute value of item corresponding to key.

By default this just attempts to use custom_attribute.

fn typed_system_attribute<K, V>(item: &Self::ItemId, key: &K) -> Option<V>

where K: Encode, V: Decode,

Returns the strongly-typed system attribute value of item corresponding to key.

By default this just attempts to use system_attribute.

fn can_transfer(_item: &Self::ItemId) -> bool

Returns true if the item may be transferred.

Default implementation is that all items are transferable.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<F, A, AccountId> Inspect<AccountId> for ItemOf<F, A, AccountId>

where F: Inspect<AccountId>, A: Get<<F as Inspect<AccountId>>::CollectionId>,

type ItemId = <F as Inspect<AccountId>>::ItemId